Interesting works

Thanks to the authors to show us that we always have to be positive. It is not uncommon for places of events to be set on fire to erase all clues. The authors demonstrate that even after exposure to 1000 °, it is possible to find traces of blood with Luminol and especially to extract a complete DNA profile. Result they obtained for 60% of their samples.Detection of blood and DNA traces after thermal exposure(International Journal of Legal Medicine, 2017)

The authors studied the required wearing time of a garment to find a contact DNA. They estimate this time at only 2 seconds to obtain a complete profile of the handler. To this result are added the study of 3 sampling methods and how to do this samplingScientific Reports 9, 2019, 9542.

The authors compare the latest software sold by FARO to study the localization of blood sources.Forensic Science International, vol 301, 2019, pp. 166-173. It must already be taken into account that at least one of the authors is related to the commercial company FARO. Then, if these tools can accurately calculate a distance from a wall, what about the height? Whereas this dimension that remains in my opinion the most important to estimate for criminal prosecution and it is known for a long time that the mathematical method used by these tools does not give a precise value of the Height.

Artifacts caused by scavenging Diptera can lead to errors in the analysis of facts that may have occurred on the scene. This is why the confirmaiton test developed by the authors of this article brings a real added value. This test is based on the detection of cathepsin D present in the digestive juices of DipteraForensic Science International: Synergy, vol. 1, 2019, pp. 1-10.

3D CAD modeling allows you to move around freely. The way to move inside is intuitive and is based on the use of keyboard arrows. The insertion of information is infinite and allows for a simple and complete approach of the place of evidences, the results of their analyzes and even a reconstruction of facts.

Known for a long time, the use and interpretation of the results of firing residues can sometimes be confusing. The authors propose a complete review of this index. After having defined it, they present how to interpret it and what are its limitsUnderstanding Gunshot Residue Evidence and its role in Forensic Science,The American Journal of Forensic Medicine and Pathology, 2019).

The authors confirm that washing bloody cotton or polyester textiles does not obliterate the blood test on them. They studied the effects of drying time before washing, the different programmes of the washing machine, the different detergents used and even the drying temperature. They obtained positive results with the use of Luminol or COMBUR solution and even a genetic profile in 28% of these positive cases. Which makes me repeat that the first quality of a person working in Forensics is optimism!Detectability of bloodstains after machine washing International Journal of Legal Medicine, online 21 juillet 2018

After demonstrating that scientific evaluation standards are not adapted to forensic science, the authors cite some principles that I believe are essential for all experts. They highlight a minimum level of competence, a capacity to question and to express with conviction their analyses.Are Forensic Scientists Experts? Journal of Applied Research in Memory and Cognition, Vol 7 (2), 2018, pp. 199-208

The authors describe the laws of Physics that apply to the movement of traces of blood when handling a bloody object, creating the ejection model well known to all Morphoanalysts. Work that confirms that the main action of the Centrifugal Force leads to the manipulator being slightly or even not bloody as a result of the movements performed. I also hold the PDF of this article.The Dynamics of Blood Drop Release from Swinging Objects in the Creation of Cast‐off Bloodstain Patterns Journal of Forensic Sciences, 2018, online juillet 2018)

The author of the reflections on the place of judicial expertise in criminal proceedings in adversarial and inquisitorial systems highlights the continental European system. He modulates his opinion by pointing out the excessively close relationship that may exist between the Public Prosecutor’s Office and the experts, the absence of the parties at all stages of the investigation and the impossibility of carrying out a counter-expertise in certain disciplines, as is often the case in Genetics. It also raises the institutional independence that forensic science centres must have and which is not ensured in state laboratories around the world. He cites the IPSC of the University of Lausanne as one of the only centres meeting this requirement of autonomy.De l’expertise judiciaire dans le cadre du procès criminel et de la recherche de la vérité : quelques réflexions Revue de Droit Université de Sherbrooke, 1996-1977, vol 27 (1-2), 47 pages)

I am pleased to see that some, although they are primarily academics and not practitioners in the field, point to the need for an objective or even automatic method of identifying blood trace patterns. They develop it on impact or ejection models, both of which are composed of projections. It is since 2006 that I have been pointing out that these models are mainly differentiated by the distribution of blood traces, convergent for the impact model and linear for the ejection model. And for almost 10 years I have been using and teaching my identification key, an objective method for identifying traces of blood already well known in the Animal and Plant Worlds.An automated approach to the classification of impact spatter and cast-off bloodstain patternsForensic science Inernational, 2018, 289, pp 310-319)

The authors focus on the limitations and vulnerabilities of decision-making under significant conditions of uncertainty. Emphasizing emotional and cognitive biases, they develop the influence they can have on the reliability of forensic results. Finally, they indicate that a scientific basis would be useful in determining the value of evidence and therefore forensic analysis.Examining the Role of Science in the Courtroom: Admissibility and reliability of forensic science Albany law review, 2018).

The authors remind me of a case in which I was involved and for which I was able to differentiate menstrual blood from peripheral blood. They offer the TEICHMANN test. This test is already well known in our environment as a test to confirm the blood origin of the sample, it would give a negative result for menstrual blood. If this result is confirmed, the differentiation would become very simple.Detection and comparaison of normal and menstruel Blood sangles found at crime scene International Journal of Current research in Life Sciences, 2018, vol 07 (06), pp2233-2236)

The authors show us that we must always believe in it. Indeed, despite walls that have been plastered and repainted up to 6 times, it is possible to find traces of blood. To do this, they highlight a preparation of the area to be treated by moistening it before using a Luminol solution. They even obtained DNA profiles in 74% of cases after this preparatory action.Detectability, visualization, and DNA analysis of bloodstains after repainting the walls (International Journal of Légal Medicine 2018, pp1-10)

We have been hearing for a long time why bloody clues should be allowed to dry, why they should not be stored in plastic bags. The authors explain why and propose the best attitudes to have according to the nature of the bloody support.Medecine Science International Medical Journal (2018)

My methodology provides that to determine a chronology between two bloody sequences, I must find at least one interaction between traces of each sequence. The authors offer us a significant help to determine the direction of the interaction between a passive trace and a contact transfer.Visual characteristics for sequencing of overlapping bloodstain patterns (Forensic Science International, mars 2018)

I am happy to read that I am no longer the only one advocating a methodology organized around two themes, Identification and Analysis, which follow one another to make the expert conclusions as objective as possible. Journal of Forensic Sciences 63 (1), p. 341, 2018. This organization allowed me to obtain ISO 17020 accreditation in 2014, which no other organization has yet obtained.

Today it is possible to highlight fingerprints on fruits (apple, tomato) and vegetables (onions, potato) with at least three types of powders including simple black powder. If we except the tomato, this highlighting remains possible at least 2 weeks after deposition.The Visualization of latent fingerprints on fruits and vegetables(Journal of Emerging Forensic Sciences Research Vol 2 (2)).

It is common for the individual identified as a wearer to indicate that he or she has lent his or her clothing to another person and that the latter has not left his or her DNA there. The authors allow us to advance in this thorny issue of determining the clothing wearer through DNA through experience including up to three wearers. And as they conclude, it is extremely rare that we do not find the DNA of a wearer, even if the wearing of the garment was brief, 10min for example.Impact of several wearers on the persistence of DNA on clothes—a study with experimental scenarios (International Journal of Legal Medicine, NOv. 2017: pp1-7)

In recent years, various authors have focused on the study of traces on clothing, demonstrating that the alteration by the fabric of these traces makes them difficult to interpret (What we already knew from earlier publications: BRIGGS-1978 KARGER-1998, SLEMKO, 2003). Human obstinacy makes them continue their studies without solving the real problem of the nature of the fabric that damages the outline of the trace and without answering questions, was the clothing worn? if so, by a spectator or an aggressor? And above all, by not taking into account that the morphoanalyst will more seriously study the traces that stain the neighbouring walls of the possibly soiled protagonists.Chapter Seven – Forensic Interpretation of Bloodstains on Fabrics (Forensic Textile Science, 2017 : pp127-167)

The possibility for the expert to be biased in the rendering of these results is an opportunity that has concerned me for years and has led me to develop methods related to this perspective. This is why I could only welcome the work of the authors, who demonstrate to us through 403 experts from 21 countries that the bias is not sufficiently taken into account.Cognitive Bias and Blindness: A Global Survey of Forensic Science Examiners(Journal of Applied Research in Memory and Cognition, Nov. 2017)

The authors introduce the use of X-ray fluorescence (MA-XRF) for the detection of human traces and gunshot residue on large surfaces such as complete clothing or walls. This technique also allows in high resolution to give the order of shots with different ammunition. X-rays also make it possible to find an impact signature even if it is covered by multiple layers of wallpaper or blood. Large area imaging of forensic evidence with MA-XRF (Scientific Reports 7, Article number: 15056, 2017)

This work shows the effectiveness of using Raman spectroscopy to non-destructively analyze blood traces, highlighting specific changes over time up to two years. The observed changes in spectra over time were consistent with known biochemical processes that occur when blood ages naturally, and these variations were sufficient to allow differentiation and predictions of time from deposition to 2 years with an overall accuracy of ~70%.Predicting the time of the crime: Bloodstain aging estimation for up to two years(Forensic Chemistry, Vol 5, Sept 2017: pp 1-7)

If the level of gene methylation is a function of the person’s age, the authors show that from traces of blood, they have identified the level of methylation of selected genes and thus determined the person’s age with a maximum error of 6 years and this over a panel of 82 women aged 18 to 91 years.Methylation Status and Human Age at ree Autosomal Loci: A New Forensic Pro ling Tool (Journal of Forensic and Crime Studies, Nov 2017, Vol 1 (1))

A theoretical model describing the distribution of blood spatter resulting from a blunt bullet is proposed based on Rayleigh-Taylor instability (responsible for the sizes of blood drops generated and their initial velocity) and the effects of gravity and friction. Today, this model is theoretical, but I know Daniel ATTINGER well enough to know his desire to discover a model applicable in the real world.Hydrodynamics of back spatter by blunt bullet gunshot with a link to bloodstain pattern analysis (Physical Review Fluids 2, July 2017)

The fingerprint brush is well known for its potential for cross-contamination between evidence, highlighting the risk of using the same fingerprint brush on multiple surfaces inside and between crime scenes. The authors indicate a method of cleaning these brushes by using a solution containing 1% bleach and 5% Virkon (DNA decontamination of fingerprint brushes, Forensic Science International May 2017)

Recent advances in drone technology have not only facilitated its access but also reduced the cost of aerial imagery. The authors show the prospects of 3D modelling with low-end technology based on three simulations of outdoor forensic scenes involving a manikin, skeletal remains and artificial blood were built in an abandoned quarry. The results showed that the tool is effective in searching for dispersed body parts but is insufficient for less easily identifiable evidence, such as traces of blood. These were only detected after they had been properly marked by human action.Using drone-mounted cameras for on-site body documentation: 3D mapping and active survey(Forensic Science International, Oct 2017)

The action of flies at a bloody crime scene, feeding on the blood present, regularly leads to misinterpretation by the Morphoanalyst who is not aware of this action. This is why Christopher Dwen conducted his thesis on this subject proposing to add to the morphological criteria already studied, the study of external factors influencing the distribution of traces, the shape and color of each trace. What the experienced Morphoanalysts are already doing (Dwen, C. J.L., 2017).Alteration of bloodstain patterns by Diptera: objective analysis based on Wonder’s 2001 criteria(Masters Thesis of Bournemouth University)

The perpetrators can set fire to destroy the evidence. It is accepted that blood and especially DNA are no longer usable beyond a temperature of 1000°C. However, following their work, the authors conclude that even after exposure to a maximum temperature of 1000°C, complete DNA was obtained on 60% of the traces. That is why we must pay the same attention to burnt scenes as to others. You always have to look, that’s often how you find it!Detection of blood and DNA traces after thermal exposure(International Journal of Legal Medicine, Oct 2017: pp. 1-9)

The kastel-Meyer test also called the KM is widely used in Genetics to confirm the blood origin of the index. This publication shows the deleterious action of one of these components on DNA. This is why this test must be carried out on only part of the unanalyzed trace or else another confirmatory test such as the one proposed by the authors of this study must be used.Kastle-Meyer blood test reagents are deleterious to DNA(Forensic Science International, oct. 2017)

The authors highlight Green Leucomalachite, indicating that it is the most suitable test to test the blood origin of a sample, with the fewest false positives. They even indicate that LMV should replace Benzedine. I remind you that these two products are highly toxic, today benzidine is only used in France under a hood. If the LMV has few false positives, light is one, which induces a certain reaction in a house for example. It should be added that the reaction medium of the LMV is very acidic, making it very altering for DNA analysis.Presumptive tests: A substitute for Benzidine in blood samples recognition(Forensic Sciences International Genetics)

DNA methylation is increasingly recognized for its potential use in age prediction. In this study, the author prediction model based on three CpG sites in three methylation markers was able to predict the age for liquid blood samples over 5 years.Evaluation of DNA methylation-based age prediction on blood(Forensic Science International Genetics, Oct 2017).

In order to make the identification of blood trace models robust and objective, I have developed for several years a process for identifying blood trace models based solely on morphological criteria of the traces studied and the supports on which they are found.Bloodstain Pattern Identification Key

The evaluation conducted on behalf of the U.S. federal standards body indicates that the tools currently in use are not satisfactory. The interest of authorization makes the authors propose a new technique based on automatic learning (ConNets).Automated latent fingerprint recognition

For those who can read German, I think this article is interesting. I proposed to its author to come and present his work at the European Morphoanalysis Conference in Poland, for which I am the scientific coordinator.(Rechtsmedizin 2017, pp 1–5)

Here is a book that will provide an approach to the Baysian networks that are increasingly used in the argumentation of analytical results. Designing and Understanding Forensic Bayesian Networks using Argumentation dspace.library.uu.nl

The authors propose a method based on tryptophan contained in the vitreous humor to determine the postmortem delay. Their study gives interesting results. To be continuedJournal of Forensic Sciences, février 2017

Without waiting for the validation of their method, the authors reveal that RAMAN spectroscopy can be used to determine the type of dry blood traces. A portable RAMAN will then be able to determine in situ the identification of fluids with information such as race, gender, etc. Analytical Chemistry, December 23, 2016

The authors studied the accuracy of the FARO Focus3D laser scanner to determine the area of origin of projections following percussion. The results enter a tennis ball even if the deformation of the traces as a function of the curvature of the soiled surface cannot be determined IABPA news, 32 (2):pp. 21-26

This thesis studies the interest of taking the smallest projections (<3mm) to determine the 3D position of the blood source. Master of Forensic Science de Brinda Salaskar. This interesting work also shows the limits of this method on a real stage and therefore the relevance of my Limiting Angles method.

The authors develop a tool to simulate the dispersion of blood traces following a ballistic shooting. They find little difference between their reconstruction and their testing. However, using a 100ml plastic bag of blood for their tests, they conceal the potential action of bone and organic debris from a ballistic injury.Indian Journal of Forensic Médecine & Toxicology, 2017 11(1): pp. 239-249

The authors, known for their involvement in the study of blood traces on tissues, confirm the significant influence of this type of support on traces of blood contaminating it. This is why interpretation based solely on traces of blood contaminating tissues remains difficult or even impossible today.IABPA news 32(2): pp. 15-20

The authors studied the behaviour of a drop of water on impact on a hard surface by varying the impact velocity and Weber number. This allows a better understanding of the blood trace found on the scenes studied.55th AIAA Aerospace Sciences meeting, 2017

The authors propose a smartphone application: Smart Forensic Phone to date blood thanks to its coloration linked to the presence of deoxygenated hemoglobin Sensors and Actuators B: Chemical, 243, pp 221-225But I didn’t find it on the Play Store of my phone, maybe in 2017.

The Combur3 Test® E (Roche Diagnostics Corporation) is a presumptive test based on TMB to identify blood. The exploitation of this molecule began in forensics in the 1950s but still does not seem to discriminate against human blood.Forensic Chemistry

The author provides us with a statistical evaluation of the identification of DNA mixtures through a real case studyTopics on Methodological and Applied Statistical Inference, Art of the series Studies in Theoretical and Applied Statistics pp 173-180

Fingerprints remain the simplest way to identify the presence of an individual at a fact scene. So the development of software by our Indian colleagues to exploit these fingerprints by automatic identification systems is important. International Journal of Innovative technologies, Vol 4 (8), 2016, pp: 1504-1510

The communication of statistical results in court remains a challenge. The study of our colleagues gives us tools to improve this transmission. Feel free to ask me for the full article.Journal of Forensic Identification, 2016, Vol. 66 (5), pp. 405-425

Our American colleague compares two techniques often used for tool marks and bloody fingerprints. AccuTrans seems to give more information. Feel free to ask me for the full article. Journal of Forensic Identification, 2016, Vol. 66 (5), pp. 381-387

Document established, based on the work of our Mexican colleagues, which sets up a standardization of fingerprint disclosure techniques on all types of surfaces as part of a multidisciplinary crime scene investigation action (July-September 2016)VISIÓN CRIMINOLÓGICA-CRIMINALÍSTICA

Although everyone is familiar with back-projection, few are familiar with the phenomenon. Then the theoretical model proposed by the authors could make it possible to better identify these traces in the diversity of projections that may be present at a crime scene. American Physic Society Division of Fluid Mechanics Annual Meeting in Portland, Oregon, USAConférencele 21 novembre à 10:40

The article describes a promising and non-invasive method of estimating human age. This is the calculation of the pulp-tooth ratio of the central incisor of the jawbone for which, among the software used, AutoCAD and Adobe Photoshop are the most accurate.S Basoya, VC Vinod, P Nath, AD Bhogte :Estimation of Age by Pulp-Tooth Area ration using Three Computer aided software’s– Quality in Primary Care (2016) 24 (4): 161-166).

The publication “Evaluation of forensic DNA mixture evidence: protocol for evaluation, interpretation, and statistical calculations using the combined probability of inclusion” presents a working protocol for DNA mixtures for which the validation of the expert’s interpretation may be problematic..BMC Genetics 2016, 17:125

THANK YOU to Erin Houston for her work and thesis “The effects of various laundering factors on the recoverability of DNA” published by Wright State University (Ohio – USA). It demonstrates that DNA can be found with standard extraction techniques after the use of cleaning products or machine cleaning (Chapters 2, 3) and that DNA transfers into the machine are possible (Chapter 4).Thèse

The FastDNA technique allows a genetic profile to be obtained in one hour. This validation conducted in the United States by Angelo Della Manna’s team and soon published in the FSI Genetics, shows the seriousness of the technique.FSIGEN 1578